Frequently Asked Questions

.ch is the top-level domain name for
Switzerland.
“Huh?”, you say…. Well, though this is a
small country (population about 8 million), there are four national
languages, in each of which the country has a different name:

German:

Schweiz

French:

Suisse

Italian:

Svizzera

Romansch:

Svizra

On bank notes and official documents there's plenty of room to
include all the different languages, but coins, license plates,
and domain names lack the real estate so the abbreviation of the Latin name
“Confoederatio Helvetica”
(Swiss Confederation) is used,
which avoids giving preference to any of the national languages.
Hence the “.ch” domain
name, postal code, and country stickers on automobiles.
China is .cn, by the way, and Chile
is .cl.
But why Switzerland?

What's this Librorum gibberish? Can't you speak English?

Can't you speak Latin? Index Librorum Liberorum is Latin for “List of Free Books”,
which seemed an excellent title for a site consisting primarily
of public-domain software and documents. It is a parody,
of course, of Index Librorum Prohibitorum,
the list of books banned by the Roman Catholic Church.
Liberorum is itself a Latin pun, meaning both free
of charge and promoting liberty.

Can I link to your site?

Certainly! You needn't ask permission. Just go ahead and make
the link.

Oops…wrong hemisphere! You're thinking of
Fermilab, the
Fermi National Accelerator Laboratory at Batavia,
Illinois in the United States. Yes, since physics, including
the very
highest energy particles is an interest of mine, I
enjoyed the pun on “Fermilab”, but that wasn't the only
reason…. Some day we'll get around to building that
Large Neutrino Collider in the basement. Still, there's
some radioactive stuff here.

Fourmi is French for “ant” (derived
from the Latin formica). So "Fourmilab" is “ant
laboratory”. As it happens, I've been interested in
artificial life since the mid-1970s, long before it became respectable.
Ants and ant colonies always seemed to me to be the most
interesting models, since they exhibited complex emergent
behaviour with simple organisms and a limited number of
chemical signals. When
Rudy Rucker
and I were discussing his “Artificial Life Lab” program, I
often urged him to adopt an ant colony model for it.
Being a science fiction writer, he had his revenge upon me.
The villain of his 1994 novel
The Hacker and the Ants
was based on me, with the final scene set in the building
which now contains the www.fourmilab.ch server. But he laughs best who
writes last.
Amusingly, not long after the publication of
The Hacker and the Ants, the largest
interconnected network of ant colonies known as of that date was
discovered in the Jura mountains, not far from Fourmilab.

But are there actually any robots running rampant at Fourmilab?

Not at the moment. But if you're interested in unleashing
autonomous mobile robots yourself at home, check out the Swiss made
desktop-scale (50 mm diameter) Kephera and the compatible six-wheeled
Koala from
K-Team.
Both are programmable in GNU C and other
languages, equipped with a variety of sensors, and expandable with
accessories such as grippers, vision sensors, and radio modems. I am
an investor in K-Team.

I was forced to remove my E-mail address from pages on this site
for two reasons, both regrettable. First, any E-mail address on
a Web page is quickly “harvested” by spam (unsolicited
commercial E-mail) robots and becomes unusable due to the
volume of junk mail which arrives. Second, publishing one's
E-mail address on pages as frequently visited as many
on this site, and as likely to pop out of a search engine
when lazy students seek answers to homework problems on the
Web, guarantees you'll be bombarded with dozens, if not
hundreds, of clueless questions every day. I've
published a collection of genuine E-mail which merited
my Titanium
Cranium Award. Anybody who seriously wants
to get in touch should be able to figure out my E-mail
address; the rest I don't have the time to deal with.
You can always use our notorious
feedback
form.

A number of the documents on this site cite, as references, books you're
unlikely to find at your local booksellers'. This site, as an
Amazon.com associate, allows you to order these books on-line, for
delivery anywhere on Earth. We receive a small credit when you buy
a book we recommend from Amazon—if you have a Web page,
you can do
the same for books you mention.
Any revenue we receive from Amazon is a tiny fraction of the
cost of operating this site; the main reason we link to Amazon is
to provide access to books—if you prefer to buy them elsewhere,
that's fine.

As many of the topics discussed in pages here are rather obscure,
it's inevitable some of the books they cite are out of print. I've
found
abebooks.com
an invaluable resource for tracking down and buying such
volumes. Their database connects you directly to booksellers
worldwide, and allows you to choose a suitable edition, price,
and condition before forwarding your order to the bookshop for
fulfillment. If you can't find it there, the book you're
seeking is in all likelihood extremely rare. We are an
abebooks.com affiliate, and earn a modest commission
when you order books through their site.

I downloaded a file from your
site and my unzip program says it is corrupted. What's
going on?

You are probably using
Microsoft Internet Explorer, which randomly truncates
downloads before they are complete, then serves the incomplete
file from its browser cache for subsequent download attempts,
all without any warning.
See “Corrupted Downloads”:
What Is to Be Done? for an explanation of the problem
and suggestions on how to avoid it in the future.

No. This is a noncommercial site; there's nothing for sale here, including
advertising on our pages. We do participate in associate programs as mentioned
above, but these allow us complete control over the links on the site and
handle all billing and collection of revenue.

For twenty-two years, I hosted Fourmilab with servers on-site.
Originally, the site was hosted on a Sun workstation, then
two generations of Sun servers. The site then migrated to
Dell servers, and eventually a server farm with three servers
with redundant load balancers as a front-end which could divert
traffic in case of a server failure.

As of January 10th, 2016, Fourmilab has been hosted at
Amazon Web Services,
(AWS) which provides a Linux/Apache environment which provides me
complete control over the configuration. Moving Fourmilab's hosting
to AWS has reduced the cost of hosting the site by a factor of fifty
compared to local hosting and has reduced the anxiety when leaving
town, since the Amazon-hosted site can be administered from anywhere
in the world and has high availability and hardware redundancy.
Backup is provided by mirroring the site to other AWS regions which
can be activated if the primary site goes down or in the event of
a bad asteroid day, and by regularly mirroring the site to the
local in-house server which is backed up daily.

Keep on programming, of course!
Unscheduled electrical power outages are extremely rare in Switzerland;
we've experienced less than an hour total at this site since 1992. Much
more worrisome is when things suddenly get too bright. We're
located on a plateau at an altitude of about 800 metres above sea level; in the summer
we experience frequent violent thunderstorms, with an average of
about four nearby lightning strikes per year which get into the power and telephone lines.
Circumstances like these require comprehensive power
protection, and we've found the Smart-UPS series
Uninterruptible Power Sources (UPS) from
American Power Conversion
do the job superbly. Since installing APC Smart-UPS
units on all non-resistive loads in 1994, we have had zero equipment losses due
to lightning strikes and zero downtime due to transient power outages.
High-wattage equipment insensitive to power outages, such as
laser printers and copiers, are protected by APC Line-R
voltage regulator and load protection units; they provide
the protection of a UPS without the backup battery power in
case of outage.